Noticed a “white powdery ring” around an Anemone plant at the base/mulched area (see photo). I watered over a few days ago only to see it reappear. I inspected the leaves and noticed “holes” but no evidence of any moving insect creature front nor backside of leaves. Seeking help as to what this “white powdery” reappearing ring around the base/mulch could be and preferred treatment.